1

key

play
noun \ˈkē\

Definition of key

  1. 1a :  a usually metal instrument by which the bolt of a lock is turnedb :  any of various devices having the form or function of such a key a key for winding a clock

  2. 2a :  a means of gaining or preventing entrance, possession, or controlb :  an instrumental or deciding factor the key to her success

  3. 3a :  something that gives an explanation or identification or provides a solution the key to a riddleb :  a list of words or phrases giving an explanation of symbols or abbreviations a pronunciation key in a dictionaryc :  an aid to interpretation or identification :  clue a key to understanding their motivationd :  an arrangement of the salient characters of a group of plants or animals or of taxa designed to facilitate identificatione :  a map legend

  4. 4a :  a part to be depressed by a finger that serves as one unit of a keyboard; also :  a representation of such a key (such as a space delineated on a touch screen) Tiny keys on your iPhone's screen can be difficult to hit accurately. — Cherlynn Lowb :  one of the levers of a keyboard musical instrument that actuates the mechanism and produces the tonesc :  a lever that controls a vent in the side of a woodwind instrument or a valve in a brass instrument

  5. 5 :  a system of tones and harmonies generated from a hierarchical scale of seven tones based on a tonic the key of G major

  6. 6a :  characteristic style or toneb :  the tone or pitch of a voicec :  the predominant tone of a photograph with respect to its lightness or darkness

  7. 7 :  a decoration or charm resembling a key

  8. 8 :  a small switch for opening or closing an electric circuit a telegraph key

  9. 9 :  the set of instructions governing the encipherment and decipherment of messages an encryption key

  10. 10 :  a free-throw area in basketball :  free throw lane a jump shot from the top of the key

  11. 11a (1) :  cotter pin (2) :  cotterb :  a keystone in an archc :  a small piece of wood or metal used as a wedge or for preventing motion between parts

  12. 12 :  samara

keyed

play \ˈkēd\ adjective

keyless

play \ˈkē-ləs\ adjective

Origin and Etymology of key

Middle English, from Old English cǣg; akin to Old Frisian kēi key


2

key

adjective

Definition of key

  1. :  extremely or crucially important key issues a key moment in the game a key member of the staff

Examples of key in a Sentence

  1. The changes to the manuscript are being keyed by the typist.

  2. her response was perfectly keyed to the situation

Origin and Etymology of key

see 1key


3

key

verb

Definition of key

  1. transitive verb
  2. 1 :  to lock or secure with or as if with a key :  fasten: such asa :  to secure (something, as a pulley on a shaft) by a keyb :  to finish off (an arch) by inserting a keystone

  3. 2 :  to regulate the musical pitch of key the strings

  4. 3 :  to bring into harmony or conformity :  make appropriate :  attune remarks keyed to a situation

  5. 4 :  to identify (a biological specimen) by a key (see 1key 3d)

  6. 5 :  to provide with identifying or explanatory cross-references instructions keyed to accompanying drawings — John Gartner

  7. 6 :  to make nervous, tense, or excited —usually used with up was too keyed up to sleep

  8. 7 :  to enter or input (text or data) by using a keyboard keying changes to a manuscript —often used with in or into key in a password information being keyed into a database

  9. 8 :  to be essential to :  play the most important part in defense keyed the victory

  10. 9 :  to vandalize by scratching with a key someone keyed my car door

  11. intransitive verb
  12. 1 :  to use a key

  13. 2 :  to observe the position or movement of an opposing player in football in order to anticipate the play —usually used with on The middle linebacker was keying on the halfback.

  14. 3 :  to operate a machine by means of a keyboard :  keyboard

Examples of key in a Sentence

  1. He's a key player in the organization.

  2. The key question is Can we afford it?.

  3. Underline key words and phrases as you read.

  4. Their votes were key in getting the bill passed.

Origin and Etymology of key

see 1key


4

key

noun

Definition of key

  1. :  a low island or reef; specifically :  any of the coral islets off the southern coast of Florida the Florida Keys

Origin and Etymology of key

Spanish cayo, from Taino


5

key

noun

Definition of key

slang

  1. :  a kilogram especially of marijuana or heroin

Origin and Etymology of key

by shortening & alteration from kilo

Other Drug/Tobacco Terms


Key

play
biographical name \ˈkē\

Definition of Key

  1. Francis Scott 1779–1843 American lawyer and author of “The Star-Spangled Banner”


Key

biographical name

Definition of Key

  1. John (Phillip) 1961–     prime minister of New Zealand (2008–16)



KEY Defined for English Language Learners

key

verb

Definition of key for English Language Learners

  • : to enter (information) by using the keys of a computer, typewriter, etc.

  • : to have the most important part in (something)

key

adjective

Definition of key for English Language Learners

  • : extremely important


KEY Defined for Kids

1

key

play
noun \ˈkē\

Definition of key for Students

  1. 1 :  an instrument by which the bolt of a lock (as on a door) is turned or by which an engine is started

  2. 2 :  a device having the form or function of a key Can you wind the clock with the key?

  3. 3 :  the thing that is necessary or most important in doing something To learn a skill, practice is the key.

  4. 4 :  something (as a map legend) that gives an explanation :  solution

  5. 5 :  one of the levers with a flat surface that is pressed with a finger to activate a mechanism of a machine or instrument computer keys

  6. 6 :  a system of seven musical tones arranged in relation to a keynote from which the system is named the key of C


2

key

play
verb

Definition of key for Students

keyed

;

keying

  1. 1 :  to regulate the musical pitch of

  2. 2 :  to bring into harmony

  3. 3 :  to record or enter by operating the keys of a machine The cashier keyed in the price.


3

key

play
adjective

Definition of key for Students

  1. :  of great importance :  most important She is one of our key players.


4

key

play
noun

Definition of key for Students

  1. :  a low island or reef the Florida Keys


Law Dictionary

key

adjective

Legal Definition of key

  1. :  of vital importance (as in a business organization) especially so as to be specially insured to the benefit of an employer key man key employee insurance



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